Typical liquid crystal shutters include a first polarizer, a liquid crystal cell and a second polarizer having its polarization axis substantially perpendicular to the first polarizer. In its off-state, typically known as the non-energized state, the shutter transmits light. Here, the shutter's first polarizer absorbs light that is polarized parallel to its absorption axis and transmits light that is polarized perpendicular to this axis. The transmitted polarized light is then twisted 90 degrees by the liquid crystal cell in such a manner that its polarization direction becomes parallel to the transmission axis of the second polarizer allowing the light to pass through to the viewer. In the energized or on-state, the shutter absorbs light. Here, a voltage is applied to the liquid crystal cell and no twist is applied to the polarized light that is transmitted by the first polarizer, resulting in the transmitted light being absorbed by the second polarizer. Shutters of this type find applications in many fields such as liquid crystal displays, camera shutters and stereoscopic viewing devices such as stereoscopic viewing glasses.
Typical stereoscopic viewing glasses include two separate glass-based liquid crystal shutters that open and close in an alternating pattern synchronized to the image source. The shutters are typically made by laminating polarizers to the outside of the liquid crystal shutters resulting in the stereoscopic glasses having substantial weight.